Butyl bromide → 1-Butyl-1H-imidazole-4-carboxaldehyde

Participants

Reaction Steps

Imidazole-4-carboxaldehyde (10 g, 104 mmol) was added portionwise to a solution of sodium hydride (4.56 g, 60% dispersion in mineral oil, 114 mmol) in tetrahydrofuran (150 ml), and the solution stirred for 30 minutes. n-Butyl bromide (15.7 g, 114 mmol) was added portionwise, followed by 18-crown-6 (50 mg), and the reaction heated under reflux for 18 hours. Aqueous ammonium chloride solution was added to the cooled reaction and the mixture extracted with ethyl acetate (2×) and dichloromethane (2×). The combined organic extracts were then dried (MgSO4), filtered, and concentrated under reduced pressure. The residue was purified by column chromatography on silica gel, eluting with a solvent gradient of pentane:ethyl acetate (50:50 to 25:75), to give the title compound, 4.45 g, 28% yield.

Provenance & Evidence